Imitation mother-of-pearl and process of making the same



Nov. 23 1926.

E. F. HIGGINS mrrurou MOTHER-OF-PEARL AND PROCESS OF MAKING THE SAME Filed Jain. 14, 1922 INVENTOR BY ATTORNEY:

Patented N '23, 1926.

UNITED STATES PATENT OFFICE.

EDWARD I. HIGGINS, OE BROOKLYN. NEW YORK, ABSIGNOB TO JOSEPH E. MEYER BROS. INO.', OF NEW YOB K N. Y., A. CORPORATION 01 NEW YORK.

IHITATION LIOTHER-DF-PEABL AND PROCESS OI BAKING THE SAME.

Application filed nmuar u. 1922. sem 10.329340.

This invention relates to the manufacture of imitation mother-of-pearl.

The object of the invention is to produce asubstance in imitation of mother-of-pearl, which possesses the characteristic iridescence of genuine mother-of-pearl.

A further object of the invention is to provide an imitation mother-of-pearl of the character referred to wherein the iridescence is obtained, as in the case of genuine motherof-pearl, by resolving light rays into their prismatic colors, and without employment of pigments or other coloring matter.

produce animitation of the diffused sheen effects of genuine mother-of-pearl.

A further object 'is to produce iridescen effects in substances or bodies which can be employed in the manufacture of articles of commerce, and wherein such effects are ob tained in such substances or bodies in a manner similar to the natural production thereof in genuine mother-of-pearl.

A further object is to combine, in substances or bodies suitable for use in the manufacture of articles of commerce, thedrawing, and finally pointed out in the appended claims.

Various attempts have been made to produce artificially iridescent effects and play of changeable colors by the employment of pigments and other coloring matter, but

without success in really producing an iridescent effect approaching that of the genuine mother-ofearl.

It has also een attempted to produce a.

diffused effect in plastic bodies or substances, but, so far as I am aware, such efforts have failed to attain asatisfactory degree of success in producing a diffused sheen effect approaching that of genuine mother-of-pearl, and, so far as I am aware, no attempt has heretofore been made to secure the iridescent effects of genuine mother-of-pearl, and to fix and stabilize the same in a ,form or body or substance to permit the practical use thereof in the manufacture of articles of commerce, nor to combine the same with an imitation of the diffused sheen effects of mother-of-pearl, whereby there may be imparted to such articles of commerce a close semblance in effect and appearance to genuine mother-of-pearl.

In carrying out my invention I propose to produce in a suitable body or substance A further object of the invention is to the iridescent effects of genuine mother-ofpearl, in a fixed and stabilized manner, and in the same way such effects are produced in the genuine'article. I also propose to produce a body or substance having a diffused sheen effect in imitation of mother-of-pearl, and I then propose to combine the two bodies, or effects, so as to produce an imita-g tion of mother-of-pearl. It is among the special purposes of my present invention to accomplish these results economically and in a practical and commercially useful manner in the manufacture of various articles such as boxes, trays, combs, "handles for various instruments, mirror and brush backs, or the like, in fact, any article capable of being made from plastic material.

The invention is carried out in stages, in one of which the iridescent effect is attained, in-another of which the diffused sheenefl'ect is attained, and in another of which the two effects are combined and associated to produce the imitation of mother-of-pearl product, which, as above indicated, may be incorporated into various articles of commerce. t i

In carrying out the stage of producing the iridescent effect, in accordance with m invention I employ an exceedingly thin transparent film of suitable material. I have found that such a transparent film may be produced from a solution of the esters of cellulose, such as the nitrate, or the acetate. I do not desire, however, to be limited or restricted to the use of the esters of cellulose for this purp0se, as a suitable thin transparent film may also be obtained in the form of a solution of resins such as-dammar, shellac,

mastic, tr the like. It is important that the uses a plastic material which is transparent solvent element of the solution should be of is better. For other uses transparency may such nature as to be volatile, and also of such not be essential. I will refer to this plastic nature as to exert no solvent or chemical acmaterial as a base body, intending thereby to tion on the surface or body of material to include a plastic material of the nature rewhich the thin transparent film is to be apferred to, or its equivalent, whether in mass plied. 'In this connection I have found that or in sheet form, or in the form of a fashamyl acetate, acetone or otht ketonic comioned or shaped article of manufacture. bination, alcohol-ether, diacetonealcohol, and The surface of the base. body is then polthe like, are suitable solvents for use in conishe'd to a sufficiently high degree to render nection with esters of cellulose in the producthe same capable of reflecting light impingtion of a solution to be emplo ed in according thereon. Upon the polished surface of ance with my invention, an for resins I the base-body is applied or deposited in any have found that fusel oil, alcohol benzene, suitable manner a thin layer of material or the like, are suitable solvents to be em which is immiscible with the material of the ployed. In order to obtain an exceedin base body. I have found that a thin film of thin transparent film, I have found it egelatin answers the purpose, although my insirable that the solution should contain only vention is not to be limited in this respect as avery small amount of solid matter. Ihave other materials may be employed, such as found in the case of a solution of the esters agar-agar, gum ara ic, or the like. A conof cellulose, for example, that approximately venient way of applying this layer is to deone per cent of solid matter in the solution posit the same from an aqueous solution. is sufficient. I do not desire, however, to After the layer of gelatin or other matebe limited in this respect. When proper rial has dried thoroughly, the surface thereprecaution is observed inrespect to the charof is polished. For this purpose I propose actor of solvent and solid matter and relative to employ a basic halogen salt of bismuth, proportion of the latter, the application of such as oxychloride. ox bromide, or oxyiothe solution to the surface of suitable mate- ,dide of bismuth. This alogen salt of hisrial, after being treated as will be hereinafter .muth in the form of a dry powder may bemore fully described, leaves, on evaporation applied over the surface of the gelatin layer of the solvent of said solution, a smooth, in an suitable or convenient manner. I transparent, extremely thin film. This soluhave ound it satisfactory to apply the salt tion may be applied in various ways either with a soft rag, chamois, or the like. Apby flowing the same overthe surface to parently this operation not only levels, which it is to be applied, or spraying the smooths and polishes the surface of the layer same thereon, or by immersion, or otherwise. of gelatin or other material, but the minute As the solvent employed in the solution cells, pores or recesses present in the layer evaporates, the iridescent colors begin to apsti'ucture or body become filled up with the ear. p halogen salt of bismuth employed, leaving Such a thin transparent film alone is too the surface of the layer of gelatin or other delicate and frangible to permitof'being material extremely brilliant. This also handled or to be of commercial utility, and, materially aids in rendering the gelatin nontherefore, in accordance with my invention, permeable to the solvent of the thin trans- I proposeto. fix and stabilize. the sameso as parent film when the latter is applied thereto secure the iridescent effects produced in to. To this brilliant polished surface of the a permanent form, capable. of commercial gelatin layer the thin transparent film, here- ,utility in the industrial arts. This I accom-. inbefore described, is applied in the manner.

plish by specially preparing the base body set forth. to which the thin transparent film is applied, The outer surface of the thin transparent and also by suitably protecting. the surface film after being applied to the surface of of the film from injury. the layer.of gelatin, or other material, is For a base body I preferably employ a then carefully polished with one or another suitable plastic material, whether transluof the basic halogen salts of bismuth. This cent, transparent or opaque. I'have found a operation fills up or reduces any porosity in pyroxylin compound, such as celluloid, suitthesurface of the thin transparent film, and able for the purpose. I do not-desire, howrenders su'ch surface very brilliant, and ever, to be limited or restricted to the use of hence more highly. capable of reflecting celluloid or other pyroxylin compound. as light therefrom. This is important as apany well known. substitute therefor, such as parently it serves to intensify the color effect the products known commercially ascasein, produced. This operation also renders the satowlite, or the like, afl'ords an excellent thin transparent film surface non-permeable equivalent. This plastic material is employed when a, fixing and protecting coating is apin any desired form, whether, as a mass, in plied to the surface thereof. It also serves the form of a sheet, or in the basic form of an to effect a more perfect light reflection and article of .manufacture. F or-some ultimate interference efi'ect, modifyingthe,dispersion of colors throu h the blending thereof with white light re ected from its own surface and resulting interference caused by such reflection of white light with. the prismatic refracted light rays.

The next operation. is to apply a protective or fixing coating to the surface of the transparent film. The object of this operation is to protect against injury the thin transparent film, which is exceedingly fragile and very easily breakable. A coating of material which is immiscible with the mate-. rial of the transparent film should be used for the protecting coating. I have found that a coating of gelatin deposited from an aqueous solution thereof will answer the purpose. If desired, the surface of this protecting coating of gelatin may in turn be protected, as, for instance, by hardening the same, or rendering it insoluble. This may be accomplished in many different ways. I have found that the desired result may be accomplished by subjecting the surface of the protecting coating of gelatin to the action of formaldehyde vapors, orby dipping the same into a weak solution of formaldehyde, or the desired results may be attained by applying to the surface of the protecting film a thin coating of lacquer or varnish. This completes the stage of producing the iridescent effects in a fixed and stabilized condition capable of being utilized commercially. y

The resulting product, as above explained, may be either a composite sheet, which can be stamped or blanked out into sections to be incorporated into anydesired article of manufacture, or the operations .above described may be carried out upon a mass of original plastic material which itself has compound dough during the manipulation of the latter in the process of its manufacture. I have found it preferable to intro- .duce the suspended fish scale pigment at the very end of the rolling operation to which the plastic pyroxylin compound is subjected in the ordinary process of-its manufacture. It is important to apply the minimum amount of rolling action to the plastic compound after the introduction of the fish scale pigment, in order to avoid altering or changing the delicate physical structure of the organic fish scale pigment. The application .of heat to the plastic pyroxylin compound during the introduction of the fish scale pigment is also important, as it maintains the pyroxylin compound in a plasticcondition, rendering it permeable to the liquid or vehicle carrying the fish scale pigment in suspension. The pressure exerted upon the plastic and softened pyroxylin compound causes the pigment to be forced into the body of the compound and dispersed indiscriminat-cly therein. After the introduction and incorporation of the fish scale pigment into the body or mass of the plastic pyroxybeenformed into the required shape to make an article of manufacture.

The end product of this stage of operation employed in carrying out my invention presents a beautiful effect of blended, variegated and changeable colors which vary or change as the surface is turned or shifted in the light to which it is subjected. This is the beautiful iridescent effect of genuine mothcr-of-jiearl. 1

An important characteristic of this productis that no pigment or -coloring matter is employed. the iridescence or changeable color effects being obtained solely from the effects of light reflection and refraction, the intensification of such reflection and refraction and the interference of the reflected and refracted rays.

I will now describe the'stage of producing the imitation mother-of-pearl diffused or sheen effect, which is to be combined with the iridescent effect produced as above described. For this purpose the dehydrated pigment obtained from fish scales in the form of microscopically small particles preliu compound, the plastic material is carried through the ordinary remaining steps for }.u'mlucin celluloid, for example. The re-- sulting product is characterized by the presence therein of irregular translucent streaks and blotches. presenting more or less of a mottled appearance imparting a diffused. sheen remarkably-like that of natural pearl shell.

The next operation in carrying out my invention is to combine the material possessing the imitation diffused sheen ofpearl shell with thebody to Which has been imparted the iridescence of genuine motherof-pearl. "This can be. accomplished in various ways. According to one method, the material having the diffused sheen effect may be employed and .applied as a covering for the'body which has been rendered iridescent, thereby obtaining the combined effects of the iridescence and diffusion. As above ex lained, the material which has been made iridescent may have been originally shaped in the form of the article of manufacture, and the iridescent effect produced on such a blank; In that case a sheet which has been given the diffused sheen appear-- ance of pearl shell is correspondingly shaped and applied over the iridescent surface as a covering therefor.

Another way of utilizing the iridescent and sheen materials .is to shape ordinary celluloid into the form of any desired ar ticle, then in-laying on its surface a sheet which has been rendered iridescent, and finally applying over the base as well as the inlay, a covering of material to which the diffused sheeneffect has been imparted. It is to be understood, of course, that many other ways wiZl readily occur to persons skilled in the art of combining and utilizing in the industries the bodies or substances which, respectively, have been rendered iridescent and given the diffused sheen effect as above described.

If desired. instead of employing the body containing the difiused sheen effect, in combination with the iridescent body, I may simply immerse the iridescent body in, or otherwise apply, a liquid solution capable of depositing a transparent film, to which solution has been added fish scale pigment, thereby securing the desired diffused sheen effect in imitation of mother-of-pearl.

The final product in any of the above illustrations is a composite body made up of an element employed as a core or base,"so to speak, and which'has been rendered beautifully iridescent, and a covering of fish scaleplastic composition which supplies the mother-of-pearl diffused sheen effect, producing in the blending and combining of these effects of iridescence and diffusion the beautiful appearance of natural mother-ofpearl.

In carrying out my invention, I am en-' abled to attain with facility and econom? a body or substance in imitation mother-o pearl, in which the iridescent effects are at tained without the use of pigments or 'colf ors, but purely from the efiects of light interference. I am enabled to obtain this re sult in. a composition or body which is moldable, or otherwise workable, into any desired shape in the production of articles of manufacture. Any desired article ca= pable of being made out of celluloid or plastic composition such as celluloid, may be roduced in the use thereof. In this respect produce an imitation mother-of-pearl which possesses very remarkable practical and commercial advantages over the real mother-of-pearl, in that the latter is necessarily fragile, whilev articles produced as above described are strongly resistant :;of injury through fracture or breakingl' 'More over, articles to be produced from" real mother-of-pearl are necessarily prescribed in size, whereas articles of any desired size, such as are ordinarily made out of pyroxy lin compound, may be produced with materials such as I have described. I am thus enabled to produce articles of commerce in imitation of mother-of-pearl, and possessing remarkable fidelity of mother-of-pearl appearance, very easily and economically.

In the accompanying drawing, I have shown in Fig. 1 an illustrative example of the product according to my invention. In Fig. 2 I have indicated the method of obtaining the iridescent effect through the interference of ii ht waves. In Fig. 3 I have indicated gra ically the action obtained from a monoc lromatic light ray.

To further explain the action involved in the roduction of the iridescent efi'ect, re-

ferring to Fig. '2, let us suppose A to indicate a-source' of monochromatic light, say, yellow. ,'A t the point 1, where this light impinges a n the surface of the thin transparent ii in, a art of the yellow rays are reflected from the upper surface of the film, as ijihdicated at A, and the remainder pass on through the thin film, undergoing refraction "in such passage. Of such refracted rays a portion are reflected from the lower surface of the'film at the point a, back -.through the film, and a portion of these rays emergin at the point 2 from the upper surface of t e film as indicated at A Only a portion of the rays are reflected at the point a, the unreflected portion emerging from the lower surface of the film and pass on through the gelatin layer and are possibly subjected to other refractions and reflections, as indicated by the dotted lines until finally dissipated, but such further reflections and refractions are of such reduced intensities that they may be disregarded. At the point 2 a portion of the rays emerge, as indicated at A, while the remaining portion of reduced intensity is again reflected back through the film, to the point 6. Here again occurs a partial reflection to the goint 3, and a partial emergence at b as inicated by the dotted lines. At the point 3, a portion emerges as indicated at A while a portion is again reflected through the film to the point a, where reflectiontand emergence again take place, the reflection being to point 4, where emergence, as indicated at A, takes place, and also reflection as before, and so on, each succeedin' emergence A, A, A, A, &c., being of re uced'intensity, and appearing as bands of yellow light, in-the' instance referred to as illustrative of the operation, as graphically indi cated in Fig. 3, the bands A A A", A, .&o., corresponding to the rays A A A A, of Fig. 2, and separated from each other by spaces or bands which are black or which contain no light. I

It will be seen that the rays A have traveled a distance greater than thattraveled by rays A by about twice the thickness of the thin film; the rays A by about four times the thickness of the film; the rays SEO ence to the immediately preceding one, but

also, in increasing amount with reference to the initial reflected ray A. Ifv this retardation in the case of the ra A is onehalf the wave length of yellow ight, or any odd number of half-wave lengths, and the point of emergence is close to the point of reflection 1, then the rays A and A will neutralize each other, and hence no light will be seen. This is what takesQplace in the production of the black bands intermedi ate the rays A A, A,-&c'., of Fig. 3. If, on the other hand, the retardation is equal to a whole wave length of yellow light, or two whole'wave lengths, or any multiple of wholewave lengths," then the rays which emerge in close proximity will reinforceinstcad of neutralize each other, thereb intensifying theemerging rays, thou as above observed, the intensity of eac succeeding ray A, A, &c., is reduced for the reasons above pointed out. Now this rule of action obtains as to all the colors of the spectrum, and hence, where the initial incident light is, say, white light, or sun light,

an iridescent effect is roduced by the resulting interferences of the light waves of the resulting resolved rays, due to the retardation and action above described. This, it will be observed, is the manner in which the iridescent effects-are produced in soap bubbles, the wings of some insects, and in genuine mother-of-pearl.

Thus itwill be seem-that in securing the iridescent effects, in accordance with my invention, I follow the same plan that nature has provided for genuine mother-of-pearl, and I attain the same results, though in a practical form capable of being utilized in the industrial arts. I

The color effects obtained in accordance with my invention may be controlled and varied by var; ing the thickness of the thin transparent fi m, or by varying the thickness of the sheet or body or coatingflcontaim inghthe imitation diffused sheen effect, or

Having now set forth the objects and nature of my invention, and the manner of carrying the same into practical and useful operation, what I claim as new and useful and of my own invention, is

1. In the manufacture of imitation mother-of-pearl, the process which consists in applying a thin transparent film to alight ray reflecting surface of a plastic material, and then applying to the film a plastic composition having fish scale-pigment incorporated therein.

2. In the manufacture of imitation motherof-pearl, the process whichconsists in applying to the surface of a base body a layer parent film.

of material immiscible with said body, then applying a thin transparent film to the surface of said layer, then polishing with a his muth salt the surface of and finally applying a protecting coating to thethintrans- 3. In the manufacture of imitation mother-of-pearl, the process which consists in applying a layer of gelatin to a base body, then "polishing with a bismuth salt the surface of said gelatin, then applyin a thin transparent film to the surface of sai layer, and finally applying a protecting coating to the thin transparent film.

4. In the manufacture of imitation mother-of-pearhthe process which consists in polishing the surface of a base body, and applying to the olished surface a layer of material iinmiscib c with such body, then olishing the surface of such layer with a ismuth salt and a lying thereto a thin transparent film, an ally applying a protectin coating to the transparent film.

5. Iii the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base body, and applying to the. olished surface a layer of material immisci le with such body, then polishing with a bismuth salt the surface of such layer and appl in thereto a thin transparent film, and fina y applying a protecting coatin to the transparent film, and which is immiscible therewith.

6. In the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base body, and applying to the polished surface a layer of material immiscible with such body, then polishing with a bismuth salt the surface of such layer and applying thereto a thin transparent film, and finally applying a film of gelatin to, the transparent film.

7. In the manufacture of imitation motherbf-pearl, the process which consists in polishing the surface of a base body, and applying to the polished surface a layer of material immiscible with such body, then polishing witha bismuth salt the surface of such layer and applying thereto a thin trans arent film, and finally a plyin a film of ge atin to the transparent Im an hardening the surface of the gelatin film.

8. In the manufacture of imitation mother-of-pearl', the process which consists in polishing the surface of a base body, and applying to'the polished surface a layer of material immiscible with such body, then polishing with a bismuth salt the surface of such layer and. ap lging thereto a thin transparent film, an na ly applying a film of gelatin to the transparent film, and subjectmg the surface of the gelatin film to the action of;,formaldehyde.

9. In the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base body, and applying to the olished surface a layer of material immisci le with such body, then polishing with a bismuth salt the surface of such layer and a plying thereto a thin transparent film, and finally polishing the surface of the transparent film.

10. In the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base body, and applying to the olished surface a layer of materlal immiscib e with such body, then polishing with a bismuth salt the surface of such layer and applying thereto a thin transparent film, and finally polishing and pfotecting the surface of the transparent 11. In the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base body, and applying to the olished surface a layer of material immiscr le with such body, then polishing with a bismuth salt the surface of such layer and applying thereto a thin transparent film, and finally polishing the surface of the transparent film and applying a protecting coating thereto.

12. In the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base body, and applying to the polished surface a layer of material immiscible with such body, then polishing with a bismuth salt the surface of such layer and applying thereto a thin transparent film, and finally polishing the surface of the transparent film and applying a protecting coating of gelatin thereto.

13. In the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base body, and applying to the polished surface a layer of material immiscible with such body, then polishin with a bismuth salt the surface of such dayer and applying thereto a solution of esters of cellulose.

14. In the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base body, and applying to the polished surface a layer of material immiscible with such body, then polishing with a bismuth salt the surface of such layer and applying thereto a solution of esters of cellulose, the solvent of which is volatile and exerts no action on the surface or bod to which the solution is applied.

15. n .the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base body, and applying to the polished surface'a layer of material immiscible with such body, then polishing with a bismuth salt the surface of such layer and applying thereto a solution of esters of cellulose in a volatile ketonic solvent.

materia immisc1 le with such body, then polishing with a' bismuth salt the surface of such ayer and applying thereto a solution of esters of cellulose, and finally applying a gelatin film to the thin transparent 17. In the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base material, then appl ing to the polished surface thereof a thin ayer of material immiscible therewith, then polishing the surface of said layer with a basic halogen salt of bismuth, and finally applying a thin transparent film to the polished surface of the layer.

18. In the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a sub-plastic material, then applying to the polished surface thereof a thin layer of material immiscible therewith, then polishing the surface of said layer with a basic halo en salt of bismuth, and finally applying a thin transparent film to the olished surface of the layer.

19. n the manufacture of imitation mother-of-pearl, the process which consists in polishing the surface of a base material, then applying to the polished surface thereof a thin layer of gelatin, then polishing the surface of said gelatin layer with a basic halogen salt of bismuth, and finally applying a thin transparent film to the polished surface of the gelatin layer.

20. In the manufacture of imitation mother-of-pearl, the process which consists in polishin the surface of a base material, then applying to the polished surface thereof a thin layer of material immiscible therewith, then polishing the surface of said layer with a basic halogen salt of bismuth, and finally applying a thin transparent film to the polished'surface of the layer and protecting said thin transparent film with a gelatin coating.

21. As a new article of manufacture in imitation of mother-of-pearl, a composite body including a thin transparent film having the property of producing interference of light rays, and a covering material containing the pigment of fish scales.

22. As a. new article of manufacture in imitation of mother-of-pearl, a stable composite body formed of plastic material combining therein the effects of iridescence of genuine mother-of-pearl and a diffused sheen in imitation of mother-of-pearl.

In testimony whereof I have hereunto set my hand on this 11th day of January A.

11,1922. EDWARD F. HIGGINS. 

